✅ Top 50 JavaScript Interview Questions 💻✨
1. What are the key features of JavaScript?
2. Difference between var, let, and const
3. What is hoisting?
4. Explain closures with an example
5. What is the difference between == and ===?
6. What is event bubbling and capturing?
7. What is the DOM?
8. Difference between null and undefined
9. What are arrow functions?
10. Explain callback functions
11. What is a promise in JS?
12. Explain async/await
13. What is the difference between call, apply, and bind?
14. What is a prototype?
15. What is prototypal inheritance?
16. What is the use of ‘this’ keyword in JS?
17. Explain the concept of scope in JS
18. What is lexical scope?
19. What are higher-order functions?
20. What is a pure function?
21. What is the event loop in JS?
22. Explain microtask vs. macrotask queue
23. What is JSON and how is it used?
24. What are IIFEs (Immediately Invoked Function Expressions)?
25. What is the difference between synchronous and asynchronous code?
26. How does JavaScript handle memory management?
27. What is a JavaScript engine?
28. Difference between deep copy and shallow copy in JS
29. What is destructuring in ES6?
30. What is a spread operator?
31. What is a rest parameter?
32. What are template literals?
33. What is a module in JS?
34. Difference between default export and named export
35. How do you handle errors in JavaScript?
36. What is the use of try...catch?
37. What is a service worker?
38. What is localStorage vs. sessionStorage?
39. What is debounce and throttle?
40. Explain the fetch API
41. What are async generators?
42. How to create and dispatch custom events?
43. What is CORS in JS?
44. What is memory leak and how to prevent it in JS?
45. How do arrow functions differ from regular functions?
46. What are Map and Set in JavaScript?
47. Explain WeakMap and WeakSet
48. What are symbols in JS?
49. What is functional programming in JS?
50. How do you debug JavaScript code?
💬 Tap ❤️ for detailed answers!
1. What are the key features of JavaScript?
2. Difference between var, let, and const
3. What is hoisting?
4. Explain closures with an example
5. What is the difference between == and ===?
6. What is event bubbling and capturing?
7. What is the DOM?
8. Difference between null and undefined
9. What are arrow functions?
10. Explain callback functions
11. What is a promise in JS?
12. Explain async/await
13. What is the difference between call, apply, and bind?
14. What is a prototype?
15. What is prototypal inheritance?
16. What is the use of ‘this’ keyword in JS?
17. Explain the concept of scope in JS
18. What is lexical scope?
19. What are higher-order functions?
20. What is a pure function?
21. What is the event loop in JS?
22. Explain microtask vs. macrotask queue
23. What is JSON and how is it used?
24. What are IIFEs (Immediately Invoked Function Expressions)?
25. What is the difference between synchronous and asynchronous code?
26. How does JavaScript handle memory management?
27. What is a JavaScript engine?
28. Difference between deep copy and shallow copy in JS
29. What is destructuring in ES6?
30. What is a spread operator?
31. What is a rest parameter?
32. What are template literals?
33. What is a module in JS?
34. Difference between default export and named export
35. How do you handle errors in JavaScript?
36. What is the use of try...catch?
37. What is a service worker?
38. What is localStorage vs. sessionStorage?
39. What is debounce and throttle?
40. Explain the fetch API
41. What are async generators?
42. How to create and dispatch custom events?
43. What is CORS in JS?
44. What is memory leak and how to prevent it in JS?
45. How do arrow functions differ from regular functions?
46. What are Map and Set in JavaScript?
47. Explain WeakMap and WeakSet
48. What are symbols in JS?
49. What is functional programming in JS?
50. How do you debug JavaScript code?
💬 Tap ❤️ for detailed answers!
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*FREE Resources to Learn Web Development* 🔥
🔹️ HTML - w3schools.com/html
🔹️ CSS - web.dev/learn/css
🔹️ JavaScript - javascript.info
🔹️ TypeScript - typescriptlang.org/docs
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🔹️ UI/UX - css-tricks.com
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🔹️ Node.js - nodejs.dev
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🔹️ HTML - w3schools.com/html
🔹️ CSS - web.dev/learn/css
🔹️ JavaScript - javascript.info
🔹️ TypeScript - typescriptlang.org/docs
🔹️ Git - learngitbranching.js.org
🔹️ React - react.dev
🔹️ UI/UX - css-tricks.com
🔹️ API - restapitutorial.com
🔹️ Python - python.org/doc
🔹️ Node.js - nodejs.dev
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